Experimental and computational study of diffusion mobilities for fcc Ni–Cu–Mn alloys

Abstract

Based on the available thermodynamic description and experimental diffusivities, the diffusion mobilities of Ni, Cu and Mn for fcc Ni–Cu–Mn ternary alloys have been investigated in the present work. Interdiffusion coefficients for fcc Ni–Mn binary alloys with Mn content up to 60at% and for Ni-rich fcc Ni–Cu–Mn ternary alloys were measured using diffusion couple method combined with Electron Probe Micro-Analyzer (EPMA) technique. During the assessment of diffusion mobilities by means of the CALPHAD method, experimental interdiffusivities for Cu-rich fcc Cu–Mn–Ni alloys were also taken into account. Comparisons between the results calculated using the diffusion mobilities assessed in the present work and the experimental data show that a good agreement has been obtained for the diffusion data such as the diffusion coefficients, concentration profiles and diffusion paths. Thus it is believed that the diffusion mobilities for fcc Ni–Cu–Mn alloys obtained in the present work can be applied for a wide composition range.